JPS63110694A - Mathod of mounting leaded electronic component - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) The present invention relates to a method for mounting leaded electronic components on a board.

W skin Δ skin 1 Electronic circuit devices generally consist of electronic components placed on an insulating substrate on which a conductive pattern is formed, and the electronic components and the conductive pattern are electrically connected by soldering to form a circuit. FIG. 7 shows a partial cross-sectional view of a board on which leaded electronic components are mounted. In the figure, reference numeral 1 denotes an insulating substrate having lead insertion holes 1a formed therein, and conductive patterns 2 formed on both surfaces in the illustrated example. 3 is an electronic component with a lead, and a lead 4.4 is inserted into the lead insertion hole 1a. Reference numeral 5 denotes a chip electronic component, with electrodes 5a, 5a positioned at predetermined positions on the conductive pattern 2 and temporarily fixed with an adhesive 6. Solder 7 electrically and mechanically connects the conductive pattern 2 and the leads 4, 4 or electrodes 5a, 5a, and is generally immersed in a molten solder bath to mount the electronic components 3, 5 at the same time.

If an impact is applied during work on the board or when moving the board between placing the electronic component on the board and soldering it, in the case of the electronic component 3 with leads, the part may lift off from the board 1. In the case of the chip component 5, there is a problem of peeling.

Therefore, in electronic components with leads, the leads 4 should be bent as shown in Figure 8, or the free ends of the leads 4 should be crushed as shown in Figure 9 to prevent them from coming off or coming up due to vibration or impact. It's straining.

An example of lead forming shown in FIG. 8 is shown in FIG. 10. In the figure, 8 is a cutter for cutting the lead 4, and the meshing of the fixed blade 8a and the movable blade 8b causes , cut the lead 4, and then cut the movable blade 8.
b presses the lead 4 to bend the lead. This bending direction is appropriately determined by the direction in which the conductive pattern 2 is routed, the chip components, and the like.

On the other hand, the blade thickness T of the movable blade 8b determines the length from the free end of the lead, so if it is made too thin, the grip 4 will be less likely to catch on the board 1, making temporary fixation unstable. Therefore, since a movable distance M is required, the chip component 5 cannot be placed within the region where the cutter 8 is inserted.

Further, if the movable blade 8b is separated from the substrate 1, it is possible to eliminate the problem even if a chip component is placed near the leads 4, but since the bending angle of the leads 4 is also reduced, temporary fixation becomes unstable. Therefore, it is necessary to increase the travel distance fiM, and it is necessary to consider the positional relationship with respect to other leaded electronic components.

Also, on the fixed blade 8a side, it is necessary to consider the positional relationship with other electronic components.

Furthermore, even when forming the crushed portion 9 on the lead 4 as shown in FIG. 9, the end of the punch (not shown) must be brought close to the substrate 1 after cutting the lead 4, which makes it difficult to arrange the chip components, etc. There was a problem that the lead was limited, and there was also a problem that it could not be crushed sufficiently unless it was a soft metal lead such as a mild steel wire.

The 1-"-th invention has been proposed in view of the above problems, and involves inserting the lead of an electronic component with a lead into the board glue insertion hole, and separating the lead from the board at the free end by a predetermined distance. After moving the intermediate part of the lead approximately parallel to the board to provide a bent part between the intermediate part of the lead and the free end of the lead, and temporarily fixing the electronic component at this bent part, the lead and the conductive pattern formed on the board are connected. Soldering solves the above problem by fixing it.

5) In the present invention, a bent portion is formed by moving the lead intermediate portion approximately parallel to the substrate, and the posture of the lead intermediate portion to the end portion is maintained in the lead insertion direction.

Embodiments of the present invention will now be described with reference to FIGS. 1 to 4. In the figure, the same reference numerals as in FIG. 7 indicate the same parts, and the explanation will be omitted. In the figure, 10 is a lead forming jig which is a feature of the mounting method according to the present invention, and in the illustrated example, it is a rod with a hole 10a slightly larger than the diameter of the lead 4 at its upper end, and the opening of the hole 10a is tapered. 10b is formed.

First, as shown in FIG. 1, the leads 4 of the electronic component 3 are inserted into the lead insertion holes Ia of the board 1. Next, as shown in Fig. 2, insert the free ends of the leads 4, 4 into the holes 1 of the lead forming jig
0a and stop the upper surface at the middle part of the lead. At this time, the distance between the substrate 1 and the jig IO is appropriately determined based on the thickness of the substrate 1, the diameters of the lead insertion holes 1a and the leads 4, etc.

Next, as shown in FIG. 3, the lead forming jig 10 is moved approximately parallel to the substrate 1.

As a result, the lead 4 is bent at the portions (4a and 4b shown) adjacent to the lower opening edge of the lead insertion hole 1a and the opening edge of the lead forming jig IO, respectively. The amount of deformation is at the bending point 4a
, 4b is set to be larger than the diameter of the lead 4.

When the lead forming is completed in this way, the lead forming jig 10 is lowered and the leads 4 are pulled out, as shown in FIG. 4, and the electronic component 3 can be temporarily fixed.

After that, the protruding leads 4 of the board 1 are dipped in molten solder to permanently fix the electronic component 3 to the board 1 as in the conventional case.

FIG. 5 shows a modification of the lead forming jig, in which a metal ring is attached to the upper end of a rod 10' having a hole 108 through an insulating ring 11. 2 are coaxially connected, and the opening edge of the metal ring 12 is tapered.

This molding jig IO is a rod! θ′ and metal ring! The presence or absence of a lead can be detected by detecting conduction between the two.

FIG. 6 shows another modification of the lead forming jig.
The inner circumferential surface 10c of the opening of the hole 10a is made spherical, and the entrance of the hole 10a is narrowed.
When molding the lead 4 and the opening of the jig lO, there is a risk that the lead 4 will rub against the opening of the jig and the lead 4 will be scraped, and the resulting metal powder may adhere to undesired parts and cause trouble. is formed into a spherical surface, which allows the lead 4 to slide smoothly and prevents the above-mentioned trouble from occurring.

Note that the present invention is not limited to the above-mentioned embodiments; for example, the lead forming jig IO is not only moved parallel to the substrate 1, but also the opening of the lead forming jig IO is moved into the lead insertion hole 1a.
It is also possible to make an arc movement approximately centered on . Also, before removing lead 4 from jig lO! By bringing the substrate 1 closer to the substrate 1, the bending can be made more pronounced.

Furthermore, although a partial lead forming jig has been described, a clamper that directly clamps the leads may also be used.

As described above, according to the present invention, since the lead forming jig is formed by moving the middle part of the lead approximately parallel to the substrate, the lead forming jig only needs to be able to withstand the force applied during lead forming. It is sufficiently thinner than conventional cutters and crushers (for soft metal leads such as mild steel leads, it is possible to use a lead forming jig that is thinner than the diameter of the lead, and it is also possible to use a lead forming jig that is thinner than the lead diameter). Since the spacing can be made sufficiently distant, restrictions on the arrangement of chip components near the leads are relaxed, and higher-density packaging becomes possible.

[Brief explanation of the drawing]

1 to 4 are side sectional views of main parts of a board for explaining the mounting method according to the present invention, FIGS. 5 and 6 are side sectional views showing modified examples of the lead forming jig, and FIG. 7 is an electronic A side sectional view of the d part of the circuit device, FIGS. 8 and 9 are side sectional views showing a temporary fixing method for electronic components, respectively, and FIG. It is a diagram. 1... Board, 2... Conductive pattern, 3... Electronic component, 4... Lead. 'V～〕Jmu/force 1 figure $2 figure 5 figure 6 figure 8 ko whistle 9 mouthpiece]
○ Q

Claims (1)

[Claims] Insert the lead of the leaded electronic component into the lead insertion hole of the board, and move the lead middle part, which is a predetermined distance away from the board on the lead free end side, approximately parallel to the board to create a bent part between the lead middle part and the lead free end. 1. A method for mounting an electronic component with a lead, characterized in that the electronic component is temporarily fixed at the bent portion, and then the lead and a conductive pattern formed on a substrate are fixed by soldering.